:root {
  --bg-main: #0f172a;
  --bg-card: rgba(30, 41, 59, 0.85);
  --bg-element: #334155;
  --border-color: rgba(255, 255, 255, 0.12);
  --border-highlight: rgba(99, 102, 241, 0.5);
  --accent-indigo: #6366f1;
  --status-green: #10b981;
  --status-rose: #f43f5e;
  --status-amber: #f59e0b;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --font-sans: 'Plus Jakarta Sans', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: var(--font-sans); background: var(--bg-main); color: var(--text-main); min-height: 100vh; padding: 16px; display: flex; justify-content: center; }
.app-wrapper { width: 100%; max-width: 920px; }

.screen { display: none; }
.screen.active { display: block; animation: fadeIn 0.25s ease-out; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

.brand-header { text-align: center; margin-bottom: 24px; }
.badge-tag { display: inline-block; background: rgba(99, 102, 241, 0.15); border: 1px solid var(--border-highlight); color: var(--accent-indigo); font-size: 0.72rem; font-weight: 700; padding: 4px 12px; border-radius: 20px; }
.main-title { font-size: 2.2rem; font-weight: 800; }
.version-badge { background: var(--accent-indigo); font-size: 0.8rem; padding: 2px 6px; border-radius: 4px; }
.subtitle { color: var(--text-muted); font-size: 0.9rem; margin-top: 4px; }

.rules-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 12px; margin-bottom: 24px; }
.rule-card { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: 12px; padding: 16px; text-align: center; }
.rule-icon { font-size: 1.5rem; }
.rule-val { font-weight: 800; font-size: 1.1rem; }
.rule-lbl { font-size: 0.75rem; color: var(--text-muted); }

.btn { font-family: var(--font-sans); font-size: 0.9rem; font-weight: 600; padding: 12px 20px; border-radius: 8px; border: none; cursor: pointer; display: inline-flex; align-items: center; justify-content: center; gap: 8px; text-decoration: none; }
.btn-primary { background: var(--accent-indigo); color: #fff; }
.btn-outline { background: transparent; border: 1px solid var(--border-color); color: #fff; }
.btn-ghost { background: transparent; color: var(--text-muted); }
.btn-success { background: var(--status-green); color: #fff; }
.btn-lg { padding: 16px 28px; font-size: 1rem; border-radius: 12px; }
.btn-flex { flex: 1; }

.action-stack { display: flex; flex-direction: column; gap: 10px; max-width: 360px; margin: 0 auto; }
.card-box { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: 16px; padding: 24px; }
.form-box { max-width: 440px; margin: 20px auto; }
.form-group { margin-bottom: 16px; }
.form-label { display: block; font-size: 0.75rem; font-weight: 700; color: var(--text-muted); margin-bottom: 6px; }
.form-input { width: 100%; background: var(--bg-element); border: 1px solid var(--border-color); color: #fff; padding: 12px; border-radius: 8px; font-size: 0.95rem; }
.btn-row { display: flex; gap: 10px; margin-top: 20px; }

.game-header-bar { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: 12px; padding: 10px 16px; display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; flex-wrap: wrap; gap: 8px; }
.header-info-chip { display: flex; align-items: center; gap: 6px; }
.chip-label { color: var(--text-muted); font-size: 0.7rem; font-weight: 700; }
.chip-value { font-family: var(--font-mono); font-weight: 700; font-size: 1rem; }
.chip-value.timer-alert { color: var(--status-amber); }
.chip-value.highlight { color: var(--status-green); }

.step-progress-pills { display: flex; gap: 4px; }
.pill { font-size: 0.7rem; font-weight: 700; padding: 4px 8px; border-radius: 10px; background: var(--bg-element); color: var(--text-muted); }
.pill.active { background: var(--accent-indigo); color: #fff; }
.pill.done { background: rgba(16, 185, 129, 0.2); color: var(--status-green); }

.diagram-container { background: #020617; border: 1px solid var(--border-color); border-radius: 12px; padding: 16px; margin-bottom: 16px; }
.diagram-header { text-align: center; margin-bottom: 12px; border-bottom: 1px dashed var(--border-color); padding-bottom: 6px; }
.diagram-title { font-size: 0.7rem; font-weight: 700; color: var(--text-muted); }
.mer-canvas { display: flex; align-items: center; justify-content: center; gap: 8px; min-height: 120px; }
.mer-entity-group { display: flex; flex-direction: column; align-items: center; gap: 6px; min-width: 100px; }
.entity-box { background: #1e293b; border: 2px solid var(--status-green); border-radius: 6px; padding: 8px 12px; text-align: center; }
.entity-title { font-weight: 700; font-size: 0.8rem; color: var(--status-green); }
.entity-title.placeholder { color: var(--text-muted); }

.attr-container { display: flex; flex-wrap: wrap; justify-content: center; gap: 4px; max-width: 120px; }
.attr-bubble { background: var(--bg-element); border: 1px solid var(--status-amber); color: var(--status-amber); border-radius: 10px; padding: 2px 6px; font-size: 0.65rem; font-family: var(--font-mono); }
.attr-bubble.key { border-color: var(--status-rose); color: var(--status-rose); text-decoration: underline; }

.mer-connector { position: relative; flex: 1; min-width: 30px; display: flex; align-items: center; }
.mer-connector .line { height: 2px; width: 100%; background: var(--accent-indigo); }
.card-badge { position: absolute; top: -14px; left: 50%; transform: translateX(-50%); background: var(--status-rose); color: #fff; font-size: 0.65rem; padding: 1px 4px; border-radius: 4px; }

.rel-diamond { width: 50px; height: 50px; transform: rotate(45deg); border: 2px solid var(--status-rose); background: #1e293b; display: flex; align-items: center; justify-content: center; }
.rel-text { transform: rotate(-45deg); font-size: 0.6rem; font-weight: 700; color: var(--status-rose); text-align: center; }

.instruction-banner { background: rgba(99, 102, 241, 0.1); border-left: 4px solid var(--accent-indigo); padding: 10px; font-size: 0.85rem; margin-bottom: 12px; border-radius: 4px; }

.phase-card { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: 12px; padding: 16px; margin-bottom: 16px; display: none; }
.phase-card.active { display: block; }
.cols-two { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.col-box { background: rgba(15, 23, 42, 0.4); border: 1px solid var(--border-color); border-radius: 8px; padding: 10px; }
.col-title { font-size: 0.7rem; font-weight: 700; color: var(--text-muted); margin-bottom: 8px; }

.options-grid { display: flex; flex-wrap: wrap; gap: 6px; min-height: 40px; }
.opt-btn { background: var(--bg-element); border: 1px solid var(--border-color); color: #fff; padding: 8px 12px; border-radius: 6px; font-size: 0.85rem; cursor: pointer; flex: 1 1 auto; text-align: center; }
.opt-btn:hover { background: #475569; }
.opt-btn.selected { background: var(--accent-indigo); border-color: var(--accent-indigo); font-weight: 700; }
.opt-btn.key-opt.selected { background: var(--status-rose); border-color: var(--status-rose); }

.counter-badge { text-align: center; font-size: 0.75rem; color: var(--text-muted); margin-top: 6px; }
.game-nav-bar { display: flex; justify-content: space-between; gap: 10px; margin-bottom: 16px; }

.quote-box { background: rgba(99, 102, 241, 0.15); border-left: 4px solid var(--accent-indigo); padding: 12px; margin: 16px 0; font-style: italic; border-radius: 4px; font-size: 0.9rem; }
.summary-list { margin-top: 16px; display: flex; flex-direction: column; gap: 8px; }
.summary-item { background: rgba(15, 23, 42, 0.6); border: 1px solid var(--border-color); padding: 10px 14px; border-radius: 8px; display: flex; justify-content: space-between; align-items: center; font-size: 0.85rem; }
.summary-label { color: var(--text-muted); }
.summary-val { font-weight: 700; }
.badge-ok { color: var(--status-green); font-weight: 700; }
.badge-err { color: var(--status-rose); font-weight: 700; }

.modern-table { width: 100%; border-collapse: collapse; font-size: 0.85rem; margin-top: 10px; }
.modern-table th { background: var(--bg-element); color: var(--text-muted); padding: 8px 10px; text-align: left; }
.modern-table td { padding: 8px 10px; border-bottom: 1px solid var(--border-color); }

#loadingOverlay { position: fixed; inset: 0; background: var(--bg-main); z-index: 999; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 12px; }
#loadingOverlay.hidden { display: none; }
.spinner { width: 36px; height: 36px; border: 4px solid var(--border-color); border-top-color: var(--accent-indigo); border-radius: 50%; animation: spin 0.8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }